rt-thread-official/bsp/msp432e401y-LaunchPad/libraries/msp432e4/startup_system_files/system_msp432e411y.c

121 lines
4.8 KiB
C

/******************************************************************************
*
* Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com/
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the
* distribution.
*
* Neither the name of Texas Instruments Incorporated nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
******************************************************************************/
#include <stdint.h>
#include <ti/devices/msp432e4/inc/msp.h>
/*----------------------------------------------------------------------------
Define clocks
*----------------------------------------------------------------------------*/
#define __SYSTEM_CLOCK (16000000ul)
/* Update frequency to match the crystal frequency on your board */
#define XTAL_FREQ (25000000ul)
/*----------------------------------------------------------------------------
Clock Variable definitions
*----------------------------------------------------------------------------*/
uint32_t SystemCoreClock = __SYSTEM_CLOCK; /*!< System Clock Frequency (Core Clock)*/
/*----------------------------------------------------------------------------
Clock functions
*----------------------------------------------------------------------------*/
void SystemCoreClockUpdate(void) /* Get Core Clock Frequency */
{
uint32_t getClockDivider;
uint32_t getPLLMIntValue;
uint32_t getPLLNValue;
uint32_t getPLLQValue;
/* Update the default System Clock value for MSP432E4x devices */
SystemCoreClock = __SYSTEM_CLOCK;
if ((SYSCTL->RSCLKCFG & SYSCTL_RSCLKCFG_USEPLL) == SYSCTL_RSCLKCFG_USEPLL)
{
getClockDivider = (SYSCTL->RSCLKCFG & SYSCTL_RSCLKCFG_PSYSDIV_M) >> SYSCTL_RSCLKCFG_PSYSDIV_S;
getPLLMIntValue = (SYSCTL->PLLFREQ0 & SYSCTL_PLLFREQ0_MINT_M) >> SYSCTL_PLLFREQ0_MINT_S;
getPLLNValue = (SYSCTL->PLLFREQ1 & SYSCTL_PLLFREQ1_N_M) >> SYSCTL_PLLFREQ1_N_S;
getPLLQValue = (SYSCTL->PLLFREQ1 & SYSCTL_PLLFREQ1_Q_M) >> SYSCTL_PLLFREQ1_Q_S;
if ((SYSCTL->RSCLKCFG & SYSCTL_RSCLKCFG_PLLSRC_M) == SYSCTL_RSCLKCFG_PLLSRC_PIOSC)
{
SystemCoreClock = (__SYSTEM_CLOCK * (getPLLMIntValue)) / ((getPLLNValue + 1) * (getPLLQValue + 1));
SystemCoreClock = SystemCoreClock / (getClockDivider + 1);
}
else if ((SYSCTL->RSCLKCFG & SYSCTL_RSCLKCFG_PLLSRC_M) == SYSCTL_RSCLKCFG_PLLSRC_MOSC)
{
SystemCoreClock = (XTAL_FREQ * (getPLLMIntValue)) / ((getPLLNValue + 1) * (getPLLQValue + 1));
SystemCoreClock = SystemCoreClock / (getClockDivider + 1);
}
}
else
{
getClockDivider = (SYSCTL->RSCLKCFG & SYSCTL_RSCLKCFG_OSYSDIV_M) >> SYSCTL_RSCLKCFG_OSYSDIV_S;
if ((SYSCTL->RSCLKCFG & SYSCTL_RSCLKCFG_OSCSRC_M) == SYSCTL_RSCLKCFG_OSCSRC_PIOSC)
{
SystemCoreClock = __SYSTEM_CLOCK / (getClockDivider + 1);
}
else if ((SYSCTL->RSCLKCFG & SYSCTL_RSCLKCFG_OSCSRC_M) == SYSCTL_RSCLKCFG_OSCSRC_MOSC)
{
SystemCoreClock = XTAL_FREQ / (getClockDivider + 1);
}
}
}
/**
* Initialize the system
*
* @param none
* @return none
*
* @brief Setup the microcontroller system.
* Initialize the System.
*/
void SystemInit(void)
{
#if (__FPU_USED == 1)
SCB->CPACR |= ((3UL << 10 * 2) | /* set CP10 Full Access */
(3UL << 11 * 2)); /* set CP11 Full Access */
#endif
#ifdef UNALIGNED_SUPPORT_DISABLE
SCB->CCR |= SCB_CCR_UNALIGN_TRP_Msk;
#endif
SystemCoreClock = __SYSTEM_CLOCK;
}